The proposed study meets the requirements of a small grant (R03) and is submitted under the Behavioral Therapies Development program. It is conceived as a Stage 1 treatment development study. It will take place within the scientific and organizational infrastructure of the Center for Research on Adolescent Drug Abuse, a NIDA-funded treatment evaluation research center. The ultimate objective of the proposed investigation is to increase the effectiveness of drug abuse treatment for adolescent women. It aims to identify clinically relevant concomitants of adolescent drug abuse in females and males, to identify critical factors of success and failure in the treatment of substance abuse in adolescent women, and to establish a foundation for the development of a gender-sensitive family therapy. In Study 1, archived data will be used to gain an understanding of the differences between male and female adolescent substance abusers, predicting that young women referred for treatment will evidence more severe family dysfunction, and higher rates of depression than the males in our study. It's hypothesize that there will be no differences in rates of externalizing disorders. 180 adolescents, 90 females and 90 males, will participate in Study 1. A multiple regression and correlation data analytic strategy will be utilized. Study 2 is an exploratory, hypothesis generating study. It seeks to set a foundation for gender-sensitive interventions with adolescent substance abusers by analyzing the process of family therapy and identifying predictors of success for females as compared with males. Thirty-two adolescents, 16 females and 16 males, with participate in Study 2, which will employ a case analysis methodology to identify essential features of successfully treating drug abuse in adolescent women. The results of the proposed studies should not only increase understanding of young female substance abusers, but also establish avenues for future research designed to assist in developing effective strategies for treating these young people.